What Happens If The Generator Set Is Under-Loaded For A Long Time?

What happens if a diesel generator set is overloaded for a long time?

The set can operate at overload power for up to 1 hour. However, if the overload (exceeding rated power) continues for too long, the following conditions may occur:

Cooling system overheating – coolant temperature becomes too high.

Generator winding overheating – motor life is reduced.

Lubricating oil viscosity breaks down, causing low oil pressure, shortening engine life; in severe cases, premature wear and cylinder scoring may occur.

If the generator efficiency is too low or over-specified, any of the above conditions may also occur.

What happens if the generator set is under-loaded for a long time?

If the set operates at low load for an extended period, the coolant temperature cannot rise to normal levels. The oil viscosity remains high, increasing friction. This can cause poor piston ring sealing, allowing oil to enter the combustion chamber, resulting in poor combustion. Possible symptoms include:

Blue exhaust smoke (oil burning)

Black exhaust smoke (poor combustion)

Mixture of oil and diesel fuel expelled from the exhaust pipe